Project description:Sex differences in gene expression throughout development are poorly understood, especially sex-specific expression of micro RNAs. However these patterns of gene expression could have important implications in our understanding of the underlying mechanics of sex differentiation and sexual conflict. We extract mRNA and miRNA from male and female Drosophila melanogaster from three developmental timepoints, third larval instar, pupae and adults, and examine gene expression using microarrays. We found a large number of sex-biased mRNA transcripts at each stage of development, whereas sex-biased miRNA expression was low in larvae and pupae and more prevalent in adults.
Project description:Sex differences in gene expression throughout development are poorly understood, especially sex-specific expression of micro RNAs. However these patterns of gene expression could have important implications in our understanding of the underlying mechanics of sex differentiation and sexual conflict. We extract mRNA and miRNA from male and female Drosophila melanogaster from three developmental timepoints, third larval instar, pupae and adults, and examine gene expression using microarrays. We found a large number of sex-biased mRNA transcripts at each stage of development, whereas sex-biased miRNA expression was low in larvae and pupae and more prevalent in adults. We isolated 2 biological replicates of each sex at each of the three developmental timepoints and extracted mRNA and miRNA from each sample, creating 12 samples of each type of RNA which were ran on GeneChip Drosophila Genome 2.0 Affymetrix microarrays to examine mRNA expression, and GeneChip miRNA 3.0 Affymetrix microarrays to examine miRNA expression.
Project description:Pathogen bacteria infections can lead to dynamic changes of microRNA (miRNA) and mRNA expression profiles, which may control synergistically the outcome of immune responses. To reveal the role of dynamic miRNA-mRNA regulation in Drosophila innate immune responses, we have detailedly analyzed the paired miRNA and mRNA expression profiles at three time points during Drosophila adult males with Micrococcus luteus (M. luteus) infection using RNA- and small RNA-seq data. Our results demonstrate that differentially expressed miRNAs and mRNAs represent extensively dynamic changes over three time points during Drosophila with M. luteus infection. The pathway enrichment analysis indicates that differentially expressed genes are involved in diverse signaling pathways, including Toll and Imd as well as orther signaling pathways at three time points during Drosophila with M. luteus infection. Remarkably, the dynamic change of miRNA expression is delayed by compared to mRNA expression change over three time points, implying that the "time" parameter should be considered when the function of miRNA/mRNA is further studied. In particular, the dynamic miRNA-mRNA regulatory networks have shown that miRNAs may synergistically regulate gene expressions of different signaling pathways to promote or inhibit innate immune responses and maintain homeostasis in Drosophila, and some new regulators involved in Drosophila innate immune response have been identified. Our findings strongly suggest that miRNA regulation is a key mechanism involved in fine-tuning cooperatively gene expressions of diverse signaling pathways to maintain innate immune response and homeostasis in Drosophila. Taken together, the present study reveals a novel role of dynamic miRNA-mRNA regulation in immune response to bacteria infection, and provides a new insight into the underlying molecular regulatory mechanism of Drosophila innate immune responses.
Project description:Clear cell renal cell carcinomas (ccRCC) are characterized by arm-wide chromosomal alterations. Loss at 14q is associated with disease aggressiveness in ccRCC, which responds poorly to chemotherapeutics. The 14q locus contains one of the largest miRNA clusters in the human genome; however, little is known about the contribution of these miRNAs to ccRCC pathogenesis. In this regard, we investigated the expression pattern of selected miRNAs at the 14q32 locus in TCGA kidney tumors and in ccRCC cell lines. We validated that the miRNA cluster is downregulated in ccRCC (and cell lines) as well as in papillary kidney tumors relative to normal kidney tissues and primary renal proximal tubule epithelial (RPTEC) cells. We demonstrated that agents modulating expression of DNMT1 (e.g., 5-Aza-deoxycytidine) could modulate miRNA expression in ccRCC cell lines. Lysophosphatidic acid (LPA, a Lysophospholipid mediator elevated in ccRCC) not only increased labile iron content but also modulated expression of 14q32 miRNAs. Through an overexpression approach targeting a subset of 14q32 miRNAs (specifically at subcluster A: miR-431, miR-432, miR-127, and miR-433) in 769-P cells, we uncovered changes in cellular viability and claudin-1, a tight junction marker. A global proteomic approach was implemented using these miRNA overexpressing cell lines which uncovered ATXN2 as a highly downregulated target, which has a role in chronic kidney disease pathogenesis. Collectively, these findings support a contribution of miRNAs at 14q32 in ccRCC pathogenesis.
Project description:Sex differences in gene expression throughout development are poorly understood, especially sex-specific expression of micro RNAs. However these patterns of gene expression could have important implications in our understanding of the underlying mechanics of sex differentiation and sexual conflict. We extract mRNA and miRNA from male and female Drosophila melanogaster from three developmental timepoints, third larval instar, pupae and adults, and examine gene expression using microarrays. We found a large number of sex-biased mRNA transcripts at each stage of development, whereas sex-biased miRNA expression was low in larvae and pupae and more prevalent in adults.
Project description:Sex differences in gene expression throughout development are poorly understood, especially sex-specific expression of micro RNAs. However these patterns of gene expression could have important implications in our understanding of the underlying mechanics of sex differentiation and sexual conflict. We extract mRNA and miRNA from male and female Drosophila melanogaster from three developmental timepoints, third larval instar, pupae and adults, and examine gene expression using microarrays. We found a large number of sex-biased mRNA transcripts at each stage of development, whereas sex-biased miRNA expression was low in larvae and pupae and more prevalent in adults. We isolated 2 biological replicates of each sex at each of the three developmental timepoints and extracted mRNA and miRNA from each sample, creating 12 samples of each type of RNA which were ran on GeneChip Drosophila Genome 2.0 Affymetrix microarrays to examine mRNA expression, and GeneChip miRNA 3.0 Affymetrix microarrays to examine miRNA expression.
Project description:Using high throughput sequencing of Drosophila head RNA, a small set of miRNAs that undergo robust circadian oscillations in levels were discovered. We concentrated on a cluster of six miRNAs, mir-959-964, all of which peak at about ZT12 or lights-off. The data indicate that the cluster pri-miRNA is transcribed under bona fide circadian transcriptional control and that all 6 mature miRNAs have short half-lives, a requirement for oscillating. Manipulation of food intake dramatically affects the levels and timing of cluster miRNA transcription with no more than minor effects on the core circadian oscillator. This indicates that the central clock regulates feeding, which in turn regulates proper levels and cycling of the cluster miRNAs. Viable Gal4 knock-in as well as cluster knock-out and over-expression strains were used to localize cluster miRNA expression as well as explore their functions. The adult head fat body is a major site of expression, and feeding behavior, innate immunity, metabolism, and perhaps stress responses are under cluster miRNA regulation. The feeding behavior results indicate that there is a feedback circuit between feeding time and cluster miRNA function as well as a surprising role of post-transcriptional regulation in these behaviors and physiology.
Project description:MicroRNAs (miRNA) are small, endogenous RNAs that regulate the expression of mRNAs posttranscriptionally. Evolutionarily new miRNAs, like new protein-coding genes, are dominantly expressed in reproductive organs. To dissect the evolutionary dynamics of new miRNAs in Drosophila spp, we sequenced small RNAs from two species of Drosophila, including four samples from reproductive organs and one sample from imaginal discs / CNS. miRNA expression profile shows vast majority of new miRNAs are specifically expressed in testes and/or ovaries, suggesting a role of sexual selection for new miRNA evolution.